Ultrasound/Microbubble Targeted Delivery (UMTD) has great potential to treat solid tumors UMTD has delivered both reporter and therapeutic genes to a variety of tissues in vivo UMTD has delivered genes to tumors, but only if Microbubbles (MBs) were injected directly into the tumor prior to Ultrasound (US) treatment Several genes (such as HSV-TK) have shown to be effective at reducing the growth of tumors in other gene therapy studies.
Although there is great potential for this system, there are several limitations that need overcome—MBs used for gene therapy are not optimized for DNA binding—US delivery conditions must allow for full perfusion of the target tissue prior to destruction and insonify MBs way that transduces target tissue—Mechanism of UMTD mediated gene therapy is not entirely understood and efficiency is rather low.
The use of UMTD has several important advantages—MBs are a nonviral delivery platform that can be used repeatedly, and are likely to be safe—US can spatially target expression of the transgene—MBs can load genes, RNA, oligos, drugs, or a mix, making this a very flexible delivery platform